No offense, but i read someone who tested it without using brickblocker, dont know if its true, although i do know brickblocker and regionfrii are way over-used, because for half of the NTSC game its recommended to use, which i didnt and the games still worked fine, the only games i've used brickblocker on so far are super paper mario and Mario Galaxy which were Both NTSC

The new firmware won't do you any harm. If you burn a brickblocked version, you'll need to burn another unmodified version as well, and then do the 15% trick. However, if you burn an ISO with the update modified, you will only need to burn one disc and it'll work right away.

I'm curious about the need to specify a layer break, I didn't have to do this previously with the Caravan DVD9 JAP release of Brawl, is there any reason why the US dump needs to have the layer break set in IMGBurn.

I was under the impression that IMGBurn worked it out automatically for you, and I think it was only specifically some modchips that required this to be set or the game had issues.

For reference I am using a Wiikey with v1.9g, can anyone confirm it works without setting the layer break?